Almost all handheld electronic devices in the marketplace today are delivered with a power supply or transformer to either power the device or recharge the battery.
The transformers job is to ensure that the device or battery receive the proper power input for its particular needs. Because each device is unique the power requirements are unique with the end result being that consumers of these devices collect a wide range of transformers in many different sizes and shapes. These transformers oftentimes take the form of a brick with two cords, where one cord attaches to a standard electrical outlet and the other attaches to the device.
The transformers invariably collect in ones home and results in many tangled wires.